Is a stand with fans better?

Fans use up valuable battery life. Aluminum Heat sinks are important in electronic applications because they absorb the heat to avoid overheating and malfunction. Generally the fans attached to most cooling stands are inexpensive and are prone to breaking down and damage. Start saving your battery and lifespan of your hard drive without any fans!

Why not make the stand out of perforated aluminum?

Perforated aluminum will not cool your laptop as much as a solid piece of aluminum.
Heat sinks are designed in such a way that the heat coming from the electrical wires and other parts that are prone to heat production will be diverted to them. So the more aluminum surface, the better.

Fast facts about aluminum:

Aluminum is a common choice for heat sinks because of its relatively high thermal conductivity.
Thermal conductivity of aluminum is about three times greater than that of steel, a property that makes aluminum an important material for both cooling and heating applications. This in turn allows your notebook to run at a lower temperatures and ultimately a longer lifespan.